From: Sasha Levin <sashal@kernel.org>
To: stable@vger.kernel.org
Cc: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>,
Heikki Krogerus <heikki.krogerus@linux.intel.com>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Sasha Levin <sashal@kernel.org>
Subject: [PATCH 6.6.y 3/7] usb: typec: ucsi: split read operation
Date: Fri, 4 Sep 2026 11:58:42 -0400 [thread overview]
Message-ID: <20260904155846.1071149-3-sashal@kernel.org> (raw)
In-Reply-To: <20260904155846.1071149-1-sashal@kernel.org>
From: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
[ Upstream commit 467399d989d799433ec7dd8da2ebbfbc70207d03 ]
The read operation is only used to read fixed data at fixed offsets
(UCSI_VERSION, UCSI_CCI, UCSI_MESSAGE_IN). In some cases drivers apply
offset-specific overrides. Split the read() operation into three
operations, read_version(), read_cci(), read_message_in().
Tested-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20240627-ucsi-rework-interface-v4-3-289ddc6874c7@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ sashal: Reduced backport -- upstream 467399d989d79 touches 7 file(s), this
backport carries 6. Not backported here:
drivers/usb/typec/ucsi/ucsi_yoga_c630.c
This note is generated from the file lists only; see the resolution record
for the reasoning. ]
Stable-dep-of: eb4573cf2fd8 ("usb: typec: ucsi: use UCSI_TIMEOUT_MS for sync command completion")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/usb/typec/ucsi/ucsi.c | 20 ++++-----
drivers/usb/typec/ucsi/ucsi.h | 9 ++--
drivers/usb/typec/ucsi/ucsi_acpi.c | 64 ++++++++++++++++++++++-----
drivers/usb/typec/ucsi/ucsi_ccg.c | 28 +++++++++---
drivers/usb/typec/ucsi/ucsi_glink.c | 19 +++++++-
drivers/usb/typec/ucsi/ucsi_stm32g0.c | 19 +++++++-
6 files changed, 127 insertions(+), 32 deletions(-)
diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c
index f94ccf830cbd2..56ddedb6a44aa 100644
--- a/drivers/usb/typec/ucsi/ucsi.c
+++ b/drivers/usb/typec/ucsi/ucsi.c
@@ -46,7 +46,7 @@ static int ucsi_read_message_in(struct ucsi *ucsi, void *buf,
if (ucsi->version <= UCSI_VERSION_1_2)
buf_size = clamp(buf_size, 0, 16);
- return ucsi->ops->read(ucsi, UCSI_MESSAGE_IN, buf, buf_size);
+ return ucsi->ops->read_message_in(ucsi, buf, buf_size);
}
static int ucsi_acknowledge(struct ucsi *ucsi, bool conn_ack)
@@ -130,7 +130,7 @@ static int ucsi_exec_command(struct ucsi *ucsi, u64 cmd)
if (ret)
return ret;
- ret = ucsi->ops->read(ucsi, UCSI_CCI, &cci, sizeof(cci));
+ ret = ucsi->ops->read_cci(ucsi, &cci);
if (ret)
return ret;
@@ -1005,7 +1005,7 @@ static int ucsi_reset_ppm(struct ucsi *ucsi)
mutex_lock(&ucsi->ppm_lock);
- ret = ucsi->ops->read(ucsi, UCSI_CCI, &cci, sizeof(cci));
+ ret = ucsi->ops->read_cci(ucsi, &cci);
if (ret < 0)
goto out;
@@ -1023,8 +1023,7 @@ static int ucsi_reset_ppm(struct ucsi *ucsi)
tmo = jiffies + msecs_to_jiffies(UCSI_TIMEOUT_MS);
do {
- ret = ucsi->ops->read(ucsi, UCSI_CCI,
- &cci, sizeof(cci));
+ ret = ucsi->ops->read_cci(ucsi, &cci);
if (ret < 0)
goto out;
if (cci & UCSI_CCI_COMMAND_COMPLETE)
@@ -1050,7 +1049,7 @@ static int ucsi_reset_ppm(struct ucsi *ucsi)
goto out;
}
- ret = ucsi->ops->read(ucsi, UCSI_CCI, &cci, sizeof(cci));
+ ret = ucsi->ops->read_cci(ucsi, &cci);
if (ret)
goto out;
@@ -1530,7 +1529,7 @@ static int ucsi_init(struct ucsi *ucsi)
ucsi->ntfy = ntfy;
mutex_lock(&ucsi->ppm_lock);
- ret = ucsi->ops->read(ucsi, UCSI_CCI, &cci, sizeof(cci));
+ ret = ucsi->ops->read_cci(ucsi, &cci);
mutex_unlock(&ucsi->ppm_lock);
if (ret)
return ret;
@@ -1687,7 +1686,9 @@ struct ucsi *ucsi_create(struct device *dev, const struct ucsi_operations *ops)
{
struct ucsi *ucsi;
- if (!ops || !ops->read || !ops->sync_control || !ops->async_control)
+ if (!ops ||
+ !ops->read_version || !ops->read_cci || !ops->read_message_in ||
+ !ops->sync_control || !ops->async_control)
return ERR_PTR(-EINVAL);
ucsi = kzalloc(sizeof(*ucsi), GFP_KERNEL);
@@ -1723,8 +1724,7 @@ int ucsi_register(struct ucsi *ucsi)
{
int ret;
- ret = ucsi->ops->read(ucsi, UCSI_VERSION, &ucsi->version,
- sizeof(ucsi->version));
+ ret = ucsi->ops->read_version(ucsi, &ucsi->version);
if (ret)
return ret;
diff --git a/drivers/usb/typec/ucsi/ucsi.h b/drivers/usb/typec/ucsi/ucsi.h
index ef3ad1401070b..386b06bc7a1a0 100644
--- a/drivers/usb/typec/ucsi/ucsi.h
+++ b/drivers/usb/typec/ucsi/ucsi.h
@@ -49,7 +49,9 @@ struct dentry;
/**
* struct ucsi_operations - UCSI I/O operations
- * @read: Read operation
+ * @read_version: Read implemented UCSI version
+ * @read_cci: Read CCI register
+ * @read_message_in: Read message data from UCSI
* @sync_control: Blocking control operation
* @async_control: Non-blocking control operation
* @update_altmodes: Squashes duplicate DP altmodes
@@ -61,8 +63,9 @@ struct dentry;
* return immediately after sending the data to the PPM.
*/
struct ucsi_operations {
- int (*read)(struct ucsi *ucsi, unsigned int offset,
- void *val, size_t val_len);
+ int (*read_version)(struct ucsi *ucsi, u16 *version);
+ int (*read_cci)(struct ucsi *ucsi, u32 *cci);
+ int (*read_message_in)(struct ucsi *ucsi, void *val, size_t val_len);
int (*sync_control)(struct ucsi *ucsi, u64 command);
int (*async_control)(struct ucsi *ucsi, u64 command);
bool (*update_altmodes)(struct ucsi *ucsi, struct ucsi_altmode *orig,
diff --git a/drivers/usb/typec/ucsi/ucsi_acpi.c b/drivers/usb/typec/ucsi/ucsi_acpi.c
index ef18611282de5..c0c5746117343 100644
--- a/drivers/usb/typec/ucsi/ucsi_acpi.c
+++ b/drivers/usb/typec/ucsi/ucsi_acpi.c
@@ -46,8 +46,7 @@ static int ucsi_acpi_dsm(struct ucsi_acpi *ua, int func)
return 0;
}
-static int ucsi_acpi_read(struct ucsi *ucsi, unsigned int offset,
- void *val, size_t val_len)
+static int ucsi_acpi_read_version(struct ucsi *ucsi, u16 *version)
{
struct ucsi_acpi *ua = ucsi_get_drvdata(ucsi);
int ret;
@@ -56,7 +55,35 @@ static int ucsi_acpi_read(struct ucsi *ucsi, unsigned int offset,
if (ret)
return ret;
- memcpy(val, ua->base + offset, val_len);
+ memcpy(version, ua->base + UCSI_VERSION, sizeof(*version));
+
+ return 0;
+}
+
+static int ucsi_acpi_read_cci(struct ucsi *ucsi, u32 *cci)
+{
+ struct ucsi_acpi *ua = ucsi_get_drvdata(ucsi);
+ int ret;
+
+ ret = ucsi_acpi_dsm(ua, UCSI_DSM_FUNC_READ);
+ if (ret)
+ return ret;
+
+ memcpy(cci, ua->base + UCSI_CCI, sizeof(*cci));
+
+ return 0;
+}
+
+static int ucsi_acpi_read_message_in(struct ucsi *ucsi, void *val, size_t val_len)
+{
+ struct ucsi_acpi *ua = ucsi_get_drvdata(ucsi);
+ int ret;
+
+ ret = ucsi_acpi_dsm(ua, UCSI_DSM_FUNC_READ);
+ if (ret)
+ return ret;
+
+ memcpy(val, ua->base + UCSI_MESSAGE_IN, val_len);
return 0;
}
@@ -99,30 +126,45 @@ static int ucsi_acpi_sync_control(struct ucsi *ucsi, u64 command)
}
static const struct ucsi_operations ucsi_acpi_ops = {
- .read = ucsi_acpi_read,
+ .read_version = ucsi_acpi_read_version,
+ .read_cci = ucsi_acpi_read_cci,
+ .read_message_in = ucsi_acpi_read_message_in,
.sync_control = ucsi_acpi_sync_control,
.async_control = ucsi_acpi_async_control
};
static int
-ucsi_zenbook_read(struct ucsi *ucsi, unsigned int offset, void *val, size_t val_len)
+ucsi_zenbook_read_cci(struct ucsi *ucsi, u32 *cci)
{
struct ucsi_acpi *ua = ucsi_get_drvdata(ucsi);
int ret;
- if (offset == UCSI_VERSION || UCSI_COMMAND(ua->cmd) == UCSI_PPM_RESET) {
+ if (UCSI_COMMAND(ua->cmd) == UCSI_PPM_RESET) {
ret = ucsi_acpi_dsm(ua, UCSI_DSM_FUNC_READ);
if (ret)
return ret;
}
- memcpy(val, ua->base + offset, val_len);
+ memcpy(cci, ua->base + UCSI_CCI, sizeof(*cci));
+
+ return 0;
+}
+
+static int
+ucsi_zenbook_read_message_in(struct ucsi *ucsi, void *val, size_t val_len)
+{
+ struct ucsi_acpi *ua = ucsi_get_drvdata(ucsi);
+
+ /* UCSI_MESSAGE_IN is never read for PPM_RESET, return stored data */
+ memcpy(val, ua->base + UCSI_MESSAGE_IN, val_len);
return 0;
}
static const struct ucsi_operations ucsi_zenbook_ops = {
- .read = ucsi_zenbook_read,
+ .read_version = ucsi_acpi_read_version,
+ .read_cci = ucsi_zenbook_read_cci,
+ .read_message_in = ucsi_zenbook_read_message_in,
.sync_control = ucsi_acpi_sync_control,
.async_control = ucsi_acpi_async_control
};
@@ -163,7 +205,9 @@ ucsi_dell_sync_control(struct ucsi *ucsi, u64 command)
}
static const struct ucsi_operations ucsi_dell_ops = {
- .read = ucsi_acpi_read,
+ .read_version = ucsi_acpi_read_version,
+ .read_cci = ucsi_acpi_read_cci,
+ .read_message_in = ucsi_acpi_read_message_in,
.sync_control = ucsi_dell_sync_control,
.async_control = ucsi_acpi_async_control
};
@@ -191,7 +235,7 @@ static void ucsi_acpi_notify(acpi_handle handle, u32 event, void *data)
u32 cci;
int ret;
- ret = ua->ucsi->ops->read(ua->ucsi, UCSI_CCI, &cci, sizeof(cci));
+ ret = ua->ucsi->ops->read_cci(ua->ucsi, &cci);
if (ret)
return;
diff --git a/drivers/usb/typec/ucsi/ucsi_ccg.c b/drivers/usb/typec/ucsi/ucsi_ccg.c
index 17e94f98fff25..185d67745a540 100644
--- a/drivers/usb/typec/ucsi/ucsi_ccg.c
+++ b/drivers/usb/typec/ucsi/ucsi_ccg.c
@@ -515,11 +515,26 @@ static void ucsi_ccg_nvidia_altmode(struct ucsi_ccg *uc,
}
}
-static int ucsi_ccg_read(struct ucsi *ucsi, unsigned int offset,
- void *val, size_t val_len)
+static int ucsi_ccg_read_version(struct ucsi *ucsi, u16 *version)
{
struct ucsi_ccg *uc = ucsi_get_drvdata(ucsi);
- u16 reg = CCGX_RAB_UCSI_DATA_BLOCK(offset);
+ u16 reg = CCGX_RAB_UCSI_DATA_BLOCK(UCSI_VERSION);
+
+ return ccg_read(uc, reg, (u8 *)version, sizeof(*version));
+}
+
+static int ucsi_ccg_read_cci(struct ucsi *ucsi, u32 *cci)
+{
+ struct ucsi_ccg *uc = ucsi_get_drvdata(ucsi);
+ u16 reg = CCGX_RAB_UCSI_DATA_BLOCK(UCSI_CCI);
+
+ return ccg_read(uc, reg, (u8 *)cci, sizeof(*cci));
+}
+
+static int ucsi_ccg_read_message_in(struct ucsi *ucsi, void *val, size_t val_len)
+{
+ struct ucsi_ccg *uc = ucsi_get_drvdata(ucsi);
+ u16 reg = CCGX_RAB_UCSI_DATA_BLOCK(UCSI_MESSAGE_IN);
struct ucsi_capability *cap;
struct ucsi_altmode *alt;
int ret;
@@ -528,9 +543,6 @@ static int ucsi_ccg_read(struct ucsi *ucsi, unsigned int offset,
if (ret)
return ret;
- if (offset != UCSI_MESSAGE_IN)
- return ret;
-
switch (UCSI_COMMAND(uc->last_cmd_sent)) {
case UCSI_GET_CURRENT_CAM:
if (uc->has_multiple_dp)
@@ -607,7 +619,9 @@ static int ucsi_ccg_sync_control(struct ucsi *ucsi, u64 command)
}
static const struct ucsi_operations ucsi_ccg_ops = {
- .read = ucsi_ccg_read,
+ .read_version = ucsi_ccg_read_version,
+ .read_cci = ucsi_ccg_read_cci,
+ .read_message_in = ucsi_ccg_read_message_in,
.sync_control = ucsi_ccg_sync_control,
.async_control = ucsi_ccg_async_control,
.update_altmodes = ucsi_ccg_update_altmodes
diff --git a/drivers/usb/typec/ucsi/ucsi_glink.c b/drivers/usb/typec/ucsi/ucsi_glink.c
index 56214527fe8e2..9427693b9593c 100644
--- a/drivers/usb/typec/ucsi/ucsi_glink.c
+++ b/drivers/usb/typec/ucsi/ucsi_glink.c
@@ -117,6 +117,21 @@ static int pmic_glink_ucsi_read(struct ucsi *__ucsi, unsigned int offset,
return ret;
}
+static int pmic_glink_ucsi_read_version(struct ucsi *ucsi, u16 *version)
+{
+ return pmic_glink_ucsi_read(ucsi, UCSI_VERSION, version, sizeof(*version));
+}
+
+static int pmic_glink_ucsi_read_cci(struct ucsi *ucsi, u32 *cci)
+{
+ return pmic_glink_ucsi_read(ucsi, UCSI_CCI, cci, sizeof(*cci));
+}
+
+static int pmic_glink_ucsi_read_message_in(struct ucsi *ucsi, void *val, size_t val_len)
+{
+ return pmic_glink_ucsi_read(ucsi, UCSI_MESSAGE_IN, val, val_len);
+}
+
static int pmic_glink_ucsi_locked_write(struct pmic_glink_ucsi *ucsi, unsigned int offset,
const void *val, size_t val_len)
{
@@ -216,7 +231,9 @@ static void pmic_glink_ucsi_connector_status(struct ucsi_connector *con)
}
static const struct ucsi_operations pmic_glink_ucsi_ops = {
- .read = pmic_glink_ucsi_read,
+ .read_version = pmic_glink_ucsi_read_version,
+ .read_cci = pmic_glink_ucsi_read_cci,
+ .read_message_in = pmic_glink_ucsi_read_message_in,
.sync_control = pmic_glink_ucsi_sync_control,
.async_control = pmic_glink_ucsi_async_control,
.update_connector = pmic_glink_ucsi_update_connector,
diff --git a/drivers/usb/typec/ucsi/ucsi_stm32g0.c b/drivers/usb/typec/ucsi/ucsi_stm32g0.c
index 4454d60b9a680..e39a3ef662268 100644
--- a/drivers/usb/typec/ucsi/ucsi_stm32g0.c
+++ b/drivers/usb/typec/ucsi/ucsi_stm32g0.c
@@ -358,6 +358,21 @@ static int ucsi_stm32g0_read(struct ucsi *ucsi, unsigned int offset, void *val,
return 0;
}
+static int ucsi_stm32g0_read_version(struct ucsi *ucsi, u16 *version)
+{
+ return ucsi_stm32g0_read(ucsi, UCSI_VERSION, version, sizeof(*version));
+}
+
+static int ucsi_stm32g0_read_cci(struct ucsi *ucsi, u32 *cci)
+{
+ return ucsi_stm32g0_read(ucsi, UCSI_CCI, cci, sizeof(*cci));
+}
+
+static int ucsi_stm32g0_read_message_in(struct ucsi *ucsi, void *val, size_t len)
+{
+ return ucsi_stm32g0_read(ucsi, UCSI_MESSAGE_IN, val, len);
+}
+
static int ucsi_stm32g0_async_control(struct ucsi *ucsi, u64 command)
{
struct ucsi_stm32g0 *g0 = ucsi_get_drvdata(ucsi);
@@ -445,7 +460,9 @@ static irqreturn_t ucsi_stm32g0_irq_handler(int irq, void *data)
}
static const struct ucsi_operations ucsi_stm32g0_ops = {
- .read = ucsi_stm32g0_read,
+ .read_version = ucsi_stm32g0_read_version,
+ .read_cci = ucsi_stm32g0_read_cci,
+ .read_message_in = ucsi_stm32g0_read_message_in,
.sync_control = ucsi_stm32g0_sync_control,
.async_control = ucsi_stm32g0_async_control,
};
--
2.53.0
next prev parent reply other threads:[~2026-09-04 15:58 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-09-03 12:40 FAILED: patch "[PATCH] usb: typec: ucsi: use UCSI_TIMEOUT_MS for sync command" failed to apply to 6.6-stable tree gregkh
2026-09-04 15:58 ` [PATCH 6.6.y 1/7] usb: typec: ucsi: move ucsi_acknowledge() from ucsi_read_error() Sasha Levin
2026-09-04 15:58 ` [PATCH 6.6.y 2/7] usb: typec: ucsi: simplify command sending API Sasha Levin
2026-09-04 15:58 ` Sasha Levin [this message]
2026-09-04 15:58 ` [PATCH 6.6.y 4/7] usb: typec: ucsi: rework command execution functions Sasha Levin
2026-09-04 15:58 ` [PATCH 6.6.y 5/7] usb: typec: ucsi: inline ucsi_read_message_in Sasha Levin
2026-09-04 15:58 ` [PATCH 6.6.y 6/7] usb: typec: ucsi: extract common code for command handling Sasha Levin
2026-09-04 15:58 ` [PATCH 6.6.y 7/7] usb: typec: ucsi: use UCSI_TIMEOUT_MS for sync command completion Sasha Levin
2026-09-10 1:36 ` [PATCH 6.6.y] " Huang Wei
2026-09-11 11:21 ` Sasha Levin
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